How can transparency be maintained when using imagecopymerge in PHP to overlay images with different opacity levels?

When using imagecopymerge in PHP to overlay images with different opacity levels, transparency can be maintained by using imagecopymerge_alpha function instead. This function allows for the merging of images while preserving the transparency of the overlay image. By specifying the alpha value for the overlay image, you can control the opacity level of the overlay.

function imagecopymerge_alpha($dst_im, $src_im, $dst_x, $dst_y, $src_x, $src_y, $src_w, $src_h, $pct){
    $cut = imagecreatetruecolor($src_w, $src_h);
    imagecopy($cut, $dst_im, 0, 0, $dst_x, $dst_y, $src_w, $src_h);
    imagecopy($cut, $src_im, 0, 0, $src_x, $src_y, $src_w, $src_h);
    imagecopymerge($dst_im, $cut, $dst_x, $dst_y, $src_x, $src_y, $src_w, $src_h, $pct);
}